This invention relates generally to techniques for interconnecting electronic components and, more particularly, to backplane wiring for large electronic systems and subsystems, such as computers and the like.
Large electronic systems and subsystems are generally assembled from many smaller electronic components, such as integrated-circuit (IC) chip packages mounted on multilayer printed circuit boards. This modular construction greatly simplifies the manufacture, installation and maintenance of these systems. The IC chip packages and multilayer printed circuit boards are typically interconnected with each other by some type of backplane wiring. One conventional type of backplane wiring that is frequently used is a large circuit board having edge card connectors into which the multilayer printed circuit boards are plugged. This type of backplane wiring is generally referred to as a "mother" board. Another conventional type of backplane wiring that is frequently used relies on these same edge card connectors, but instead of a "mother board," the edge card connectors are interconnected with each other by cable harnesses.
Although these conventional types of backplane wiring have certain advantages, they also have several disadvantages. One disadvantage is that the insulated metal wires and coaxial cables used in the cable harnesses contribute a large amount of capacitance and inductance to the system, thus limiting the high speed operation of the system. Moreover, cable harnesses and their connectors can add as much as twenty-five percent to the weight and volume of the system and can also add considerably to the cost.
Another disadvantage of these conventional types of backplane wiring is that they rely heavily on soldered connections. As a result, simple modifications to the system, such as a change in the input/output configuration of a circuit board, will generally require new backplane wiring or at least major rework of the backplane wiring. This is usually very expensive and time consuming and, in many cases, the rework must be done by the manufacturer of the backplane wiring.
Accordingly, there has been a need for an improved type of backplane wiring that eliminates or at least minimizes the disadvantages of these conventional types of backplane wiring. The present invention is directed to this end.